The Centers for Disease Control and Prevention (CDC), in conjunction with the White House Office of National Drug Control Policy (ONDCP), is issuing this Health Advisory to notify public health professionals, clinicians, laboratorians, and people at risk for overdose about increasing reports from U.S. jurisdictions detecting medetomidine in the illegal drug supply and a severe withdrawal syndrome due to medetomidine exposure. Medetomidine (also known as ‘rhino tranq,’ ‘mede,’ or ‘dex’) is not approved for human use but is approved for sedation and analgesia in dogs. Its dextro-isomer, dexmedetomidine, is approved for procedural sedation in humans. Medetomidine has been increasingly detected in law enforcement drug seizures, drug product and paraphernalia samples, and in wastewater samples, with the highest concentrations in the Northeast region. Testing of illegal drug samples and clinical specimens has identified racemic mixtures of levomedetomidine and dexmedetomidine isomers without the preservatives commonly found in medical or veterinary formulations, making diversion of pharmaceutical products unlikely. Since pharmaceutical-grade products contain only dexmedetomidine, these findings suggest medetomidine is being synthesized in clandestine laboratories.
Advisory: Medetomidine in the U.S. Illegal Fentanyl Supply Increasing Risk for Overdose and Severe Withdrawal Syndrome
March 24 marks World TB Day (WTD) - a day that commemorates Dr. Robert Koch’s 1882 discovery of the tuberculosis (TB) bacterium. At that time, TB was raging through Europe and the Americas, claiming the lives of one out of every seven people. Today, WTD reminds us that tuberculosis remains a global epidemic, causing nearly 1.5 million deaths each year, primarily in lower resourced countries.
TB is not only a global concern - it’s a local one. In California, about 13% of people diagnosed with TB disease die from it annually. Orange County (OC) consistently ranks third in TB cases statewide, behind Los Angeles and San Diego counties. Alarmingly, case numbers have barely declined over the past decade. In 2025, 189 active TB cases were reported in OC, a 14% increase from the previous year’s 166 cases. The good news: TB is curable, and with proper treatment, people can recover fully.
There are two forms of TB: Latent (or inactive) TBInfection (called “LTBI”) and TB disease (active TB). People with LTBI do not have symptoms, usually have a normal chest X-ray (CXR), and are not contagious. LTBI can be detected by a blood test. In most LTBI cases, the bacteria remain inactive for life, but about 10% of people will develop TB disease later - often when the immune system is weakened by age, certain medications, or medical conditions like diabetes, kidney disease, HIV, autoimmune disorders or cancer.
Treating LTBI can decrease the risk of developing TB disease by up to 90%. That is why it is critical for providers to offer treatment and for patients to accept it.
People with TB disease typically have symptoms, an abnormal CXR, and may be contagious to others. Common symptoms of TB disease in the lungs include chronic cough, fevers, chills, sweats at night and/or unexplained weight loss. TB can affect any organ of the body, and disease outside of the lungs is often harder to diagnose.
While anyone can get TB, certain groups face higher risk. About 90% of the TB cases in OC occur in people born in countries with higher prevalence of TB, but it usually occurs decades after they immigrate to the US. Among US-born individuals with TB disease, risk factors include homelessness, incarceration, substance misuse, or travel to countries with high rates of TB. Nearly half of the TB cases in Orange County occur among people aged 65 or older, as aging and other health conditions weaken immunity - increasing the risk of TB becoming active. For information on TB cases and services in Orange County please visit OC Health Care Agency - Pulmonary Disease Services.
To strengthen prevention, AB 2132, effective January 2025 - requires primary care providers to assess patients for TB risk and test those identified as at risk. Individuals born in countries with high TB rates, those with weakened immune system, people who have had close contact with someone with TB disease, or those who have experienced homelessness or incarceration should speak with their doctor about TB testing. For more details, see the California Department of Public Health (CDPH) website CDPH Questions and Answers About AB 2132 - Mandated TB Screening.
Treatment is strongly recommended for anyone who tests positive for LTBI. LTBI treatment is much shorter and easier than treatment for TB disease and may save lives. Remember: an ounce of prevention is worth a pound of cure!
Clinicians play a vital role in ending TB by screening patients at risk, while individuals who may be at risk can take charge of their health by asking their providers about TB testing.
About Dr. Helene M. Calvet Dr. Helene M. Calvet received her MD from UCLA and is board-certified in both Internal Medicine and Infectious Diseases. She has worked in the field of public health for over 25 years, having served in Long Beach as Health Officer and TB controller and in Orange County as Deputy Health Officer. Most recently, she worked in COVID response, leading a team that dealt with more than 500 outbreaks in Long Term Care Facilities, but since 2022, she has focused on TB Control. Currently, she serves as TB Controller and Medical Director of the TB Control Program in Orange County, and as TB Clinician in the Long Beach Health Department. She has published several articles, served on two Centers for Disease Control and Prevention Expert Panels and taught providers throughout Region IX and in 6 countries on public health topics.
Respiratory Syncytial Virus (RSV) transmission is continuing in California.
CDPH recommends continuing RSV immunization of eligible infants and young children with RSV monoclonal antibody products through April 30, 2026.
As of 3/7/2026, percent positivity for RSV in Orange County continues to increase week over week.
This health alert is issued to inform healthcare providers about the ongoing transmission in California of Respiratory Syncytial Virus (RSV), the most common cause for hospitalization in infants in the US. As RSV infections are likely to continue into April 2026, CDPH recommends continuing RSV immunization of eligible infants and young children with RSV monoclonal antibody products through April 30, 2026.
Measles is the most contagious diseases known—but the good news is that it is preventable. In response to recent cases reported in Orange County and across the region, the OC Health Care Agency (HCA) encourages both health care providers and community members to take simple, proactive steps to stay protected.
Below is what you need to know to keep yourself, your family, and our community safe.
Why Measles Matters
Measles spreads through the air and can linger after an infected person leaves a room. A single infectious person may expose dozens of people in public settings, including airports, entertainment venues, or even local venues.
Because measles can lead to serious complications—especially in infants, pregnant people, and individuals with severely weakened immune systems—being prepared is essential.
For Community Members: How to Stay Protected
1. Know Your Immunity Status
Everyone who has received 2 doses of MMR vaccine (Measles, Mumps and Rubella) is considered immune.
If you are not sure whether you are protected against measles, check your vaccine records or ask your health care provider.
Most people born before 1957 are generally considered immune.
People who have not received the MMR vaccine or never had measles are not protected and are at highest risk of catching measles.
2. Get Vaccinated if You Are Eligible
MMR vaccination is safe and provides excellent protection:
Children should receive two doses (first at 12–15 months, second at 4–6 years).
Adults born after 1957 should have two documented MMR doses, unless they are immune.
Vaccination is especially important before travel, attending large gatherings, or working in health care or school settings.
Special Note Around Areas with Measles
Those who are in areas with increased measles activity or planning on international travel or travel to areas with measles outbreaks and who are at higher risk (un-immunized, or individuals considered to be immunosuppressed) should consult their health care provider and consider the following:
Teens and Adults without evidence of immunity are advised to get their first dose immediately and their second dose 28 days after the first dose.
Infants 6–11 months old can get an early MMR dose before departure.
Children age 1 and older should get their first dose immediately and a 2nd dose 28 days after their first.
Note: Early MMR dose given at 6-11 months is an additional dose and is not counted as part of the routine two-dose MMR series because it may not produce a durable immune response but can provide a layer of protection for infants going to areas with increased measles activity.
3. Stay Informed
Monitor local updates from either local public health or state public health officials and respond promptly to any calls from Public Health if you may have been exposed to a case. Staying engaged and vigilant helps protect you and those around you. Knowing your immunity status and ensuring vaccination are the most effective tools we have to stop measles from spreading.
For more resources:
Learn more about Measles and schedule a Measles vaccination at My Turn CA.
About Dr. Anissa Davis Dr. Anissa Davis graduated from UCLA and Stanford University School of Medicine. She completed her family medicine at Long Beach Memorial Medical Center, and is board certified in Family Medicine. She also completed a Preventive Medicine Residency and a master’s degree in public health (MPH). She is the Medical Director for the OC Health Care Agency’s (HCA) Communicable Disease Control Division and Deputy Health Officer for the HCA. She worked in primary care, caring for infants, children and adults for more than 10 years. In addition, she has worked in local public health agencies for a decade.
